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Induction motor and sequence reactance

  1. Jun 22, 2014 #1
    Hello! This is my second post about sequence reactances. This time- its in induction motor.

    To my understanding ( once again ) -

    In any network (symmetrical or unsymmetrical) , there would be 3 components- positive sequence component, negative sequence component and zero sequence component.


    In induction motors, what do the: running reactance, starter reactance and standstill reactance mean?


    Do any one of them signify/mean the positive sequence reactance of a unsymmetrical fault system?
  2. jcsd
  3. Jun 22, 2014 #2
    BTW, a prompt reply is very much appreciated. Please and thank you!
  4. Jun 24, 2014 #3
    According to IEC 60909-0 Ch. 3.8 Asynchronous motors 3.8.1 General:
    The impedance ZM = R M + jXM of asynchronous motors in the positive- and negative-sequence systems can be determined by:
    UrM is the rated voltage of the motor;
    IrM is the rated current of the motor;
    SrM is the rated apparent power of the motor (SrM = PrM/(effrM* COSfiTM);
    PrM is the rated motor power [kW]
    effrM is the rated motor efficiency
    COSfiTM is the rated motor power factor
    ILR/IrM is the ratio of the locked-rotor current to the rated current of the motor.
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